Notes on IoT, geospatial systems, 3D in the browser, sensors and the servers that hold it all together.
One of my projects, Wralk, was developed in 2018 and focused on real-time visualization in web browsers. One of the challenges I encountered was implementing 360-degree hit testing within the scene. I eventually figured out a solution, which I’ll explain in this post. Here is demo and source code: http://wralk.azmicirit.com/demo http://wralk.azmicirit.com/villavr https://github.com/azmicirit/wralk
After a fresh installation of Ubuntu Server, I usually install and configure several popular software packages and tools. Adding Swap Space If swap space is not already configured, I recommend adding it based on the server’s available memory and workload requirements. The appropriate swap size can vary depending on the system’s needs. For example, if the server has 2 GB of RAM, you could alloca
Bluetooth (LE) 4.0+ was introduced in 2011 and it is growing day by day. Smart applications can be powered by Bluetooth with its low energy functionality. Today, many smart devices support Bluetooth LE. Low energy consumption is mainly advantage of this technology. It comes with Client-Server concept . As in picture, Client which may be your smart phone or tablet, wants data from server such as
MQTT has become a widely used messaging protocol for the Internet of Things (IoT). The first version of the protocol was authored by Andy Stanford-Clark of IBM and Arlen Nipper in 1999. It was originally designed with a focus on minimizing battery consumption and bandwidth usage while keeping the protocol lightweight. MQTT uses a publish/subscribe messaging model and runs on top of TCP/IP. Unlike
What is The Inertial Frame? In classical mechanics, inertial reference frames are assumed to be time-independent. An Earth-fixed coordinate system can be used as an approximately stationary reference frame for many practical applications. In my application, I use an FIS1100 MEMS sensor, which incorporates a 3-axis gyroscope and a 3-axis accelerometer, together with an external 3-axis magnetomete
This formula may be necessary when converting spatial coordinates to earth fixed coordinates. But always it needs a initial point to calculate all coordinates. Formula Meter as distance of 1 degree longitude x = 1 / 1000 * (111.320 * cos(deg2rad(latitude))) phi delta LAT delta LONG 0° 110.574 km 111.320 km 15° 110.649 km 107.551 km 30° 110.852 km 96.486 km 45° 111.13
There are some production notes about mongodb version 3.2 before install. https://docs.mongodb.org/manual/administration/production-notes/ Installation on Ubuntu sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv EA312927 echo "deb http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.2 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.2.list sudo apt-get u
System Requirements Hardware A minimum of 1GB of RAM is required or installation will fail. For a full planet import 32GB or more are recommended. For a full planet install you will need about 500GB of hard disk space (as of May 2015, take into account that the OSM database is growing fast). SSD disks will help considerably to speed up import and queries. On pummelzacken the complete initial im
